Heat pump apparatus



P T. JgnmrzosKl` P P 1 3,545,224 HEAT PUMP APPARATUS Dec.' sf, 1970 QSheets-Sheet l.

Filed Dec. 18, 1968 /fffffy l/VVfNf?. THOMAS J. NICOSKI f-,ATTORNEY Dec.. s, 19,70

T. J. NICOSKI HEAT PUMP APPARA'IUS` `I2y Sheets-Sheet t` Filed Dea.Y 1g, 1968 FIG. 2

FIG. 5`

ATTORNEY 'United States Patent Office.

3,545,224 Patented Dec. 8, 1970 U.s. ci. 62-262 1 claim ABSTRACT QF THE DISCLOSURE A self-contained reverse cycle heat pumpfunit employing a generally V-shaped outdoor air-to-refrigerant heat exchanger disposed deeply within the corines of a rectangular casing to mitigate the accumulation of ice and snow thereon during operation of the heat pump and to facilitate heat exchanger frosting.

Heat pumps constructed to extract heat `from atmospheric air are now in common use. These heat pumps are often employed in geographical areas wherein temperatures below freezing, i.e., below 32; F., are encountered. A most common difficulty faced during operation of heat pumps under these low temperature conditions, is the accumulation of ice, snow and frost on the outdoor heat exchanger. Under these extremely cool operating conditions the outdoor heat exchanger must be maintained substantially below the freezing temperature of water in order to extract heat from the atmosphere. If the snow and rain are permitted to impinge upon the cold outdoor heat exchanger, ice will accumulate on the heat exchanger thereby blocking passage of air therethrough. Blocking of air passages through the outdoor heat exchanger serves to reduce its heat` collecting capacity, thus reducing the heating capacity of the heat pump unit. It is therefore necessary to periodically defrost the outdoor heat exchanger to reopen these air passages.

My invention solves many of these diiculties by placing the outdoor heat exchanger deeply within the confines of the unit casing where rain and snow are less likely to come in direct contact with surface thereof. Furthermore it permits the use of a single low cost heat exchanger which has an initial length greater than that of the area in which it is confined.

It is thus a principal object of this invention to provide the outdoor heat exchanger of an air-to-air heat pump with sufficient cover to substantially reduce the accumulation of ice and snow thereon during operation of the unit on the heating cycle and to facilitate` the removal of accumulated ice during a defrost cycle.

It is a further object of this invention to provide an outdoor heat exchanger for a heat pump which `has an initial length greater than the length of the casing in which it is disposed.

It is still another object to provide a unitary heat pump which is extremely compact and low in cost.

Other objects and advantages will become apparent as this specification proceeds to describe the invention with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a unitary heat pump employing the invention;

FIG. 2 is a plan view of the heat pump shown in FIG. 1 with the top cover removed;

FIG. 3 is a side elevation of the heat pump of FIG. 1 having a side of the unit casing removed to expose the interior thereof; and

FIG. 4 is a perspective view of the V-shaped outdoor 7 heat transfer coil employed in the unit of FIGS. 1-3.

Now referring to the drawings, heat pump unit 10 has a rectangular parallelepiped casing 11 formed by top wall 12, front wall 13, rear wall 14, iirst sidewall 15, second sidewall 16, and bottom wall 17. The chamber formed by casing 11 is divided into an outdoor section and an indoor section by a partition 18 extending from top wall 12 to bottom Wall 14 and spanning between the first and second sidewalls 15 and 16- respectively.

Rear wall 14 has a return air opening 19 and a supply air opening 20. Return air opening 19 is provided with a yiin-and-tube indoor heat exchanger 21 for modifying the temperature of the air returned from a conditioned space. Supply air opening 20 is provided with a centrifugal fan 22 for blowing the air returned through indoor heat exchanger 21 to a conditioned space via supply air opening 20.

Disposed within the outdoor section of the chamber formed by casing 11, is a V-shaped or geniculate faced outdoor heat exchanger 23. Each leg of V-shaped exchanger 23 lies in a vertical plane passing through the approximate center of the chamber formed by casing 11 and the intersection of the front wall 13 with one of the sidewalls 1'5 and 16. Heat exchanger 23 has an included angle of approximately and is most clearly shown in FIGS. 2 and 4. Heat exchanger 23 has a first group of parallel V-shaped horizontal tubes 24 spaced one above the other and a second group of parallel V-shaped horizontal tubes 25 spaced one above the other and spaced forward of said iirst group of tubes. Tubes 24 and 25 extend through a stack of spaced vertically extending substantially rectangular and planar ns 26. The ends of tubes 24 and 25 are interconnected by appropriate U- bendsto form a serpentine circuit through the heat exchanger 23. V-shaped heat exchanger 23 may be constructed in accordance with the methods outlined in copending U.S. patent applications Ser. Nos. 641,940 and 641,941, each filed on May 29, 1967 which are herein incorporated by reference.

Disposed within the bight of V-shaped heat exchanger 23 is a propeller fan and motor 28 arranged to blow air outwardly from the outdoor section of casing 11 through circular aperture 29 in front wall 13. Air enters the outdoor section by way of apertures 30 and 31 in sidewalls 15 and 16 respectively. Apertures 29, 30 and 31 are provided with appropriate grilles 32, 33, and 34 respectively to prevent foreign object from entering casing 11.

Also mounted within the outdoor section of casing 11 is a refrigerant compressor 35, four-way reversing valve 36, and a throttling means such as, for example, capillary tube 37. Compressor 35, indoor heat exchanger 21, throttling means 37, outdoor heat exchanger 23 and four-way reversing valve 36 are interconnected by a conventional reverse cycle heat pump circuit 38 (shown only in FIG. 2) whereby during the cooling and defrost cycles hot compressed refrigerant passes from compressor 35 through four-way reversing valve 36 to be condensed in the serpentine circuit of outdoor heat exchanger 23 where upon refrigerant condensate is throttled to a lower pressure by throttling means 37 into the circuit of indoor heat exchanger 21 from whence the refrigerant is evaporated and returned to the compressor 35 by four-way reversing valve 36; and whereby during the heating cycle hot compressed refrigerant from compressor 35 passes through four-way reversing valve 36 to be condensed in the circuit of indoor heat exchanger 21 Where upon the condensed refrigerant is throttled to a lower pressure by means of throttling means 37 to the serpentine circuit `of outdoor heat exchanger 23 Where the refrigerant condensate is evaporated and returned to compressor 35 by four-way reversing valve 36.

During operation of the heat pump on either the cooling or heating cycles fan 22 circulates indoor air through the indoor heat exchanger 21 to be either heated or cooled before being delivered to the conditioned space. Fan 28 also runs during the heating and cooling cycles to pass atmospheric air over the fins 26 of heat exchanger 23 whereby the refrigerant within the tubes 24 and 25 may transfer heat to or from the atmosphere. During the heating cycle the refrigerant circuit may be periodically reversed by way of four-Way valve 36 during which time fan 28 may be deactivated to permit heat exchanger 23 to defrost. The controls for operation of this heat pump have not been shown as they are considered to be conventional. However, it should be noted that the need for periodic defrosting of heat exchanger 23 is greatly reduced by placing heat exchanger 23 deeply within the contines of casing 11 where rain, sleet and snow are less likely to directly impinge and accumulate upon the surface of heat exchanger 23. It will also be noted the particular shape and disposition of heat exchanger 23, i.e. V-shaped with vertical wings, permits the use of a single low cost heat exchanger having tubes of greater length than the outdoor section of casing 11. By the use of this shape heat exchanger, positioned in the above described manner within casing 11, it will be seen that it is unnecessary to use two separate interconnected more costly heat exchangers to obtain adequate exchanger surface within the confines of the outdoor section.

Having now described in detail the preferred embodiment of my invention, I contemplate that many changes tmay be made without departing from the scope or spirit thereof and I desire to be limited only by the following claim.

I claim:

1. A refrigeration apparatus comprising: a generally rectangular casing having front, top, bottom, rear, and rst and second sidewalls; a geniculate faced iin-and-tube first heat exchanger supported on said bottom wall having rst and second wings respectively disposed in substantially vertical intersecting rst and second planes;

4 each of said first and second planes being oblique to each of said front and first and second sidewalls and substantially perpendicular to said top and bottom Walls; said iirst heat exchanger extending between said top and bottom walls; an inlet aperture in each of said sidewalls and an outlet aperture in said front wall; a propeller fan and motor assembly disposed within the bight of said rst and I second wings of said first heat exchanger and arranged to move air outwardly of said casing through said outlet aperture in said front wall; a refrigerant compressor on the side of said lirst heat exchanger opposite from said propeller fan and motor, supported on said bottom wall;

r a second fan in said casing; a partition separating said References Cited UNITED STATES PATENTS 2,342,566 2/ 1944 Wolfert 62-324 2,359,051 9/1944 Roper 62-262 2,386,883 10/ 1945 Ames 62-262 2,405,411 8/ 1946 Sybvig 62-262 2,485,733 10/ 1949 Hart 62-262 2,717,508 9/ 1955 Loveley 62-262 2,726,518 12/ 1955 Brugler 62-262 WILLIAM J. WYE, Primary Examiner U.S. C1. X.R. 62-426; 165-122 

